Improvement in cooking-stoves



UNITED STATES PATENT QFFICE.

JOSEPH D. HARDEN, OF TROY, NEW YORK, ASSIGNOR OF ONE-HALF OF HIS RIGHT TO 11 85 H. S. CHURCH, OF SAME PLACE.

I IMPROVEMENT IN COOKlNG-STOVES.

Specification forming part of Letters Patent No. 125,953, dated April 23,1872.

' fire-chamber. One part of my invention consists of the combination of parts hereinafter described whereby atmospheric air is heated and admitted into the forward or upper part of the oven and conducted from the rear lower part thereof-a lon g the under surface of the bottom plate of the oven into a chamber immediately under the grate in the bottom of the firechamber. Another part of my invention consists of the combination of parts hereinafter described whereby heated air admitted into the front part of the upper portion of the oven is mostly caused to pass directly into the lower portion of the oven and rearward therethrough to and into the exit passage at the rear end thereof. Another part consists of the means hereinafter described whereby the quantity of heated air, admitted into the oven and passing therefrom through a flue or flues along the under surface of the bottom plate of the oven into the chamber immediately under the grate in the fire-chamber can be regulated and controlled, and whereby the entrance of cold air through the said fine or flues into the oven in a reverse direction can be prevented or regulated whenever the said chamber under the firegrate shall be uncovered or opened so as to let in cold air. Another part consists of the means hereinafter described for equalizing and retaining the heat of the bottom plate of the oven when the heating-flue space extends mainly or only along the end and side portions of the under surface of that plate. Another part consists of the means hereinafter described whereby the heated air, in passing from the flue under the oven into the chamber under the firegrate, is caused to circulate in a fluespace around the removable ash-pan in the hearthpit, to increase the heat and utility of the hearth for culinary uses.

' In the accompanying drawing, Fig. l is a central longitudinal vertical section of a cookingstove which embodies the principal distinguishing features of my invention. Fig. 2 is a front elevation of a section of the same at the line z z, in Fig. 1. Fig. 3 is a horizontal section of the same at or about the line y 3 Figs. 1 and 2.

Fig. 4 is a plan of a'horizontal section of the same stove at or about the line a: m in Figs. 1 and 2, with some parts broken away. ,Fig. 5 is a central longitudinal section ofa modification of the same stove; and Fig. 6 is a horizontal section at and plan of some parts below the line to w, in Fig. 5. Figs. 7 and. 8 are central vertical sections of cooking-stoves which embody some parts of my invention.

Like parts are marked by like letters in the different figures, and the arrows therein indicate the courses of the currents of heated air through the stove.

In the drawing, A is the fire-chamber. B is the chamber immediately under the grater; in the bottom of the fire-chamber. (l is the oven. 1) is a fire-flue which extends between the oven and the top plate E, from the firechamber to v an exit-passage, w. Between the fire-chamber and the oven is an airheating space or passage, I, which communicates by an aperture or apertures, t, with'the forward part of the oven, and with the air outside of the stove by an opening or openings, 8. J is an air-heating passage extended through the top plate E and fire-tlue D and into the forward part of the upper portion of the oven in Figs. 1, 2, and 5, and into the space I in Fig. 7, and into the rear part of the upper part of the oven in Fig.8. At the rear end of the lower part of the oven is an opening, 1', into a flue, F, which extends along the under surface of the bottom plate G of the oven and communicates at its front end with the chamber B. Consequently, when the stove is in operation and the chamber B is closed against the admission of cold air the draught from the fire in the chamber A causes air to be drawn from outside the stove through the apertures 8 into the heating-space I, and from thence, in a heated state, through the openings t, into the forward part of the upper portion of the oven 0, and from the rear part of the lower portion of the oven, through the opening 4 and flue F along the under surface of the oven-bottom G, into the chamber B, and

i l l l l i thence, through the grate '12, into the fire-chamber A, so that the oven is sufficiently heated for ordinary baking purposes, and at the same time an abundance of heated air is supplied to the grated bottom of the fire'chamber to support the combustion of coal or other fuel therein with great energy and economy, without requiring any fire-flue along either the upright rear end or the bottom of the oven, and with only a single plate, H, with or without a sheetmetal lining, g, at the rear end of the oven. In Figs. 1, 5, and 7 the heated air enters the forward part of the upper portion of the oven through the passage J as well as through the passage I; and, as regards my invention, the air-heatin g passage or passages for admitting heated air into the upper or forward part of the oven, may be constructed and arranged along, or through, or in respect to, the firechamber and fire-flue of the stove in any suitable manner. In Figs. 5 and 8 the air-heating passage J extends along the middle part of the upper surface of the top plate, over the fire'flue 1). The air-heating space I in Fig. 5 extends only across the rear side of the fire-box; in Figs. 1 and 4, along one or both ends and the rear side thereof; in Fig. 8, along both the front and rear sides and one or both ends; and in Fig. 7, as a sheet-flue along the chambers A and B and fine D. In Fig. 8 there is no shelf in the oven. In Fig. 7, is a perforated shelf. But with that shelf alone the upper part of the oven is liable to be too highly heated by the hot air which enters the front part thereof, while the part of the oven below that shelf is not heated sufficiently. To obviate that defect I arrange inthe oven a shelf, K, Figs. 1, 4., and 5, with a standing shield or plate, L, at the front end of that shelf and an air-passage, 0, between the shield L and the front plate of the upper part of the oven, and leading from the .upper part of the oven into the lower part thereof, either directly, as in Fig. 5, or through an air-passage, n, Figs. 1 and 2, between the shelf K and a perforated plate, m, below that shelf, so that a large por-. tion, but not all, of the heated air which enters through one or the other, or both, of the passages I J into the forward part of the upper portion of the oven, shall be at once inter cepted by the shield L and conducted by the passage 0 into the lower portion of the oven, either directly, as in Fig. 5, or through the passage n and perforated plate m, as in Fig. 1, so as to thereby insure the proper baking of the under side of articles on the shelf K and of the upper side of articles on the oven bottom. In Fig. 8, d is a false bottom, with a sheet flue, 0, between it and plate G. The ash-pit or chamber-B has, in Figs. 1, 4, and 5, a front door, I, and a swinging cover, k, and in Figs. 7 and 8 a movable .slide, j, and in Fig. 8 a register, a, which are shown closed, but can be opened to permit access to the ash-pit, or to admit more or less cold air into the chamber B to support or assist combustion in the chamber A to any desired degree, either independently of or in connection with the aforesaid supply of heated air from the oven. M is adamp'er or register in the passage or openings between the chamber B and hot-air flue F; and when the ash-pit or chamber B is closed against the admission of cold air, the quantity of air drawn into and through the air-heating passage or passages and oven, and from the oven,through the flue F under the ovenbottom G, into the chamber B, and thence into the chamber A, by reason of the draught of the fire in the stove, can be easily regulated and controlled by means of the damper or register M, so as to thereby secure various degrees of heat in the oven and to its bottom plate G, and different rates in the combustion of the fuel in the fire-chamber, as circumstances shall require; and whenever the chamber B is open so as to let in cold air, the register M can be closed, or used to prevent or regulate the entrance of the cold air from the chamber B, through the flue F, into the oven and out through the air-heating passage or passages, in the reverse direction to the arrows in the drawing-41s may be desirable to lessen the heat in the oven when too hot for baking purposes, or to prevent or regulate the cooling of the oven whenever the hearth-pit is open.

In the stove represented in Fig. 8 the fluespace F extends-under the entire lower surface of the oven-bottom G; but to more effectually and evenly heat the bottom plate G of the oven, I arrange the flue-spaceF mainly or only across the rear and front end parts and along the side portions of the under surface of that plate, substantially as shown by Figs. 1, 2, 3,5, 6, and 7, and around a closed space, Q, which is directly under the middle portion of the plate G, and either vacant, as in Figs. 1, 2, and 3, or partly or wholly occupied by fire-brick, sand, clay, plaster of Paris, or other suitable and good heat-retaining material, as indicated at e in Figs. 5, 6, and 7 so that, while the heated air shall pass only or mainly along the'end and side portions of the bottom plate of the oven, the space Q shall materially prevent or lessen the downward radiation and conduction and waste of heat from the middle portion of that plate. .I sometimes have small openings or crevices to admit a little heated air from the flue F into the space Q, or over the material 0 therein.

In Figs. land 4 the rim of the removable ash-pan Nfits closely against the inner side of the casing of the pit in the hearth, so as to form a flue-space, 9, Figs. 1 and 3, around the ashpan, so that the heated air, in passing from the flue F into the chamber B, must pass laterally around the pan N in the flue g, and thence, through apertures h at the front side of the ash-pan, into the forward partof the chamber B, where it extends under the cover 7a of the ash-pit, so as to thereby increase the heat of the hearth and render it more useful as a warming-table when the removable ash-pan is in the pit'in the hearth.

In Figs. 5, 6, and 7 the heated air can pass from the flue F into the chamber B without passing around the removable pan N. In Fig. 8, the ashes may fall directly into the pit in the hearth, and a guard plate, f, prevents the ashes from obstructing the forward end of the flue F in case the ash-pan is removed or left out of the hearth-pit.

I am well aware that before my present invention cooking-stoves had been devised with various means fonheating fresh atmospheric air and passing the same around, or through, or along and through, or partly along and partly through, the oven, and afterward into the base of the fire-chamber; and I do not broadly claim a cooking-stove embodying any one or more of those-features.

\Vhat I claim as my invention, and desire to secure by Letters Patent, is-- 1. In combination with the fire chamber, oven, and air-heatin g passage or passages for admitting heated fresh air into the upper or forward part of the oven, the hot-air flue F, extending along the under surface of the ovenbottom G and communicating at its rear end with the oven and at its front end with the draught-chamber 13 under the fire-chamber, substantially as herein described.

2. In combination with the air-heating passage or passages for admitting heated fresh air into the forward part of the upper portion of the oven and the aperture r for discharging the heated air from the rear part of the lower portion of the oven, the combined shelf and shield K L and passage 0, arranged in the oven with or without the passage n and perforated plate an under the shelf, as herein set forth. I

3. The damper or register M arranged in the opening or passage between and in combinar tion with the chamber B under the fire-chamher, and the hot-air flue F extended under the oven-bottom and opening into the even, when the latter is furnished with means for introducing heated fresh air into the oven, substantially as described.

4. The inclosed space Q immediately under the middle portion of the bottom plate G of the oven, and either empty or partly or wholly filled by heat-retaining material 0, in combination with the heating-flue F surrounding the said space Q and extending only or mainly along the under surface of the end and side portions of the said bottom plate of the oven, as shown and described.

5. In combination with the chamber B under the fire-chamber and the draught-supplying hot-air flue F under the oven-bottom, the hot-air flue 9, Figs. 1 and 3, formed around or along and in part by the removable ash-pan N in the hearth-pit, and communicating at the rear side with the flue F and at the front side with the chamber B, where the latter extends under the cover of the hearth-pit, as herein set forth.

In testimony whereof I hereunto set my hand this 13th day of March, 1872.

JOSEPH I). HARDEN.

Witnesses: f

G. Ronnnzrson, Jr. 1 Austria E. PARK. 

